Projection lamp



Jan. 15, 1946.

E. B. NOEL PROJECTION LAMP Fig.1

EDWARD B. NOEL: I6 INVENTOR,

BY W

HIS ATTORNEY Patented Jan. 15, 1946 lTED 2,392,828-

Edward B. Noel, Cleveland Heights, Ohio, as-

signor to General Electric Companma corporation of New York Application November 4, 1944, s i Km 561,9, V I

' (Cl. l76-3d) filaims.

This invention relates to electric lamps, and is particularly concerned with combining a-lighting tube and a reflector as a projector lamp. The inof embodiment of the invention, and from the drawing.

In the drawing, Fig. 1 is a plan view of a sealed beam type oi lamp embodying the invention; and Fig. 2 is a side view of the lighting tube with a portion of the reflector in section through the axis of the lamp, as indicated by the line and arrows 2-2 in Fig. 1.

A sealed beam lamp bulb or envelope 8 is shown in Figs. 1 and 2 as comprising a rear coneave pressed glass reflector portion 2 internally surfaced with a reflective metallic coating 8, and a front radiation-transmitting cover portion t, also slightly concave and preformed out of pressed glass. The reflecting surface 3 of the rear portlon 3 is shown as a paraboloid. The parts 2, t

may be separately formed out of low-expansion heat-resistant glass such as the borosilicate glass disclosed in U. S. Patent-No. 1,304,623 tosullivan et a1... known commercially as Pyrex," and may aiterward be sealed together by fusion at suitably mating surfaces, as described in the aforesaid Wright patents. 7

Within the envelope l is mounted a lighting tube 5 wound in the form of a helical coil. This tube 3 may if desired be operated as a flash tube for photographic or other purposes. Current con nections t, i may be sealed through the reflector 2 gas and vacuum-tight as shown in'Wright Patent No. 2,324,972. As shown. the connector wires 8. i into the interior of the reflector are spaced in an axial plane, and are at equal distances to opposite sides of the reflector axis. Inside the reflector, the wires 8, i may be slightly oilset toward one another, and further inward they are bent laterally in opposite directions across the reflector 2, p rpendicular to their common plane aforementioned and substantially'parallel to one another. As shown, the helical lighting tube 5 is mounted adjacent and more or less between the laterally bent connectors 6, i, with the axis of the helix extending in the general direction of said connectors across the reflector 2, substantlally parallel with the connectors, in fact. Op-

posite sides of the helix 5 aresecured to, said connectors t, l by means of-fine ,wire' lashinss 8. An additional metal member s is shown as sealed into or through the reflector 2 similarly to the connectorsb, l, in a plane midway between and at right angles to that in which they extend inward, The wire d'extends inward at some distance to one side of the plane of the wires 6, l,

and is bent laterally across the reflector between the inward extending wires'ft, l and substantially parallel to their oppositely extending laterally bent portions, but closer to the reflector 2. Thus the laterally bent portions of the wires t, l, a form a sort of cradle extending across the lamp and the reflector 2. As shown, the lighting tube 5 is cradled and lies in this cradle against the wires 6, l, 9. As its rear side, the coiled tube 5 may be secured to the wire 9 at the bottom of the cradle by means of a fine wire lashing it laced alternately around the wire t and the convolution of the helical tube.

In the present instance, the lighting tube 5 is shown as a gaseous discharge device having electrodes ll, E2 on leads it, it sealed into its onposite ends, which are bent aside to extend in the general direction of the axis of the helix into which the tube is wound. The tube 5 may contain a working atmosphere of gas or vaporizretroverted to extend back to the leads l3, l3,

to which they are also welded. when the light ing tube 5 is of the gas discharge type, the membe: 9 may serve as a triggering inlead, and its lashing l 0 around the tube convolutions as a tri gering or starting band. As shown, external bracket terminals it are provided for the current connections 8, l, 9 behind the reflector 2. Through a rear exhaust connection indicated at it, the envelope l maybe exhausted and charged with a heat-conductive gaseous atmosphere, such as nitrogen at a pressure of 700 mm., after which the connection it may be sealed ed. 7

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In a light projector, the combination of a sealed envelope comprising a rear concave reflector portion, and a helical lighting tube mounted in said envelope with the axis of the helix in a plane substantially perpendicular to the axis of the reflector.

.V' I 7 I ,2 rgse'aeas J 22. In a light prolec'tor. the combination} or a concave :reflector; sealed through the n'eflectorgand lnslde "the-same "bent laterally to' extend transversely ofathe; re-

"iiecton'axis; and a helical'lighting tube arranzed "with themxis-oi the -helixcxtending in theidirec- 1 tion of the transverseportionsoisaid connectors in =a*planesubstantially perpendicular to slth'eaxiS or the. reflector; and current'connections thsreinto' irom thessaidaeonnectors'; said 'hel'ical ilighting tube beinzssupportcd by the transverse portions or said connectorssindependentlycirsaid cm-rent 8.1111. a light projector; the' combinaticnu'oia sealed envelope 'comprisina a rear eoncsve,..re-:

,iilector portion .and .a front transmitting porition, nptir or spaced current connectorssealed'throuzh the reflector and inside the envelope ent laterally in opposite directions across the reflector, substantially parallel with one another in'a plane;

, perpendicular -.to the axis of the reflector, a h'elicall .lightinz'tube'in said cnv'e'lopebetween said connectors was the axis oi helix sub- ,parallel'to themand thawing current ccnnectlonrtromlthe remote ;=portions or the 1 aforementioned oppositely extending connectors aback into the opposite ends of said helical tube,

andzmeans securing opposite sides-:otthehellx to said oppositely connectors independentg-ly ot connectlonl.

lnvalizhtproiector, the combination oi a ml'plfpall oi spaced "current connectors sealed through the reflector and extending inside the same 'substantlallyparallelwith one another,

another r-member sealed into the reflector bev tween" and substantially parallel to said connec- 1 tors, thus coacting with these connectors .to form a cradle; azhelically coiled-lighting tube cradled in said cradle and currentconnectlons from said current connectors-into its opposite ends, and means securing: lighting: tube insaid cradle independently-oi said current connections lntoits ends.

5. Ina lli'ght projecton'the combination 01a reflector, a pairoi spacedcurrent connectors sealed through the reflector and'inslde the-same bent laterally .in opposite directions across" the reflector, substantially parallel with one another, another member sealed .into the reflector and in- "side the same bent laterally across the reflector between/and substantially parallel to. said. op-

fpositely extending. connectors but closer to the l-reflector, 'thus'coacting with these connectors to r-Iorm; a cradle, .a. helically coiled lighting tube cradled vin said cradle and having current connections from said current connectors into its opposite ends, and means said liflltinl tubein said cradle independently og aid current connections into its ends r s .3. NOEL. 

